Simplified engine architecture and assembly

ABSTRACT

A modular engine assembly includes a cylinder bore block, a cylinder head disposed above the cylinder bore block, and a crankcase assembly disposed below the cylinder bore block. The crankcase assembly includes an upper carrier and a lower carrier each having a plurality of bearing portions therein being integral, unitary, and one-piece.

TECHNICAL FIELD

The present invention relates generally to engines and, moreparticularly, to a simplified modular engine assembly for an internalcombustion engine.

BACKGROUND OF THE INVENTION

It is known to provide an engine such as an internal combustion enginefor a vehicle such as a motor vehicle. The modern two and four cycleinternal combustion engines are an elegant and increasinglyfuel-efficient machine. Because of the wide ranging needs of vehicleowners, engines of widely different torque and power outputs must beproduced. But each different engine size (or displacement) is ofcomplicated construction and requires a large investment to design andmanufacture.

In simplest terms, these internal combustion engines typically include aplurality of pistons reciprocating within cylindrical bores andconnected to a crankshaft with connecting rods. The crankshaft issupported in the engine block by individual bearing caps. During acombustion pressure induced power stroke, each piston applies torque tothe crankshaft to provide the motive power of the engine. The torque andpower delivered through the crankshaft is a function of the pressuresurface area of the pistons and the length of their power strokes.

This assembly of pistons, connecting rods, crankshaft, and bearing capsis housed in an engine block. The engine block defines the cylinders inwhich the pistons reciprocate and it locates and supports thecrankshaft, connecting rods, and bearing caps or bearing supportsurfaces. It is open at the bottom. The pistons, connecting rods,crankshaft, and bearing caps or bearing support surfaces are assembledfrom the bottom of the block after inverting it. Finally the bottom ofthe block is closed with an oil pan. The engine block also containsengine coolant and lubricating oil passages. A cylinder head closes thetops of the cylinders in the block to define therein each respectivecombustion chamber with the enclosed piston head. The cylinder head alsocontains one or more air or fuel/air inlet ports and valves, one or moreexhaust gas ports and valves, a spark plug and, often, a fuel injector.It also contains coolant and oil passages. Both the engine block and thecylinder head are metal castings of complex design because of integratedfeatures such as coolant and oil passages. Each casting must be designedfor the specified displacement of the engine.

As observed, it is very expensive to manufacture such engines withspecifically designed and cast engine blocks and cylinder heads. Thecomplex casting requires a high capital investment manufacturingfacility for both casting and machining. As a result, making changes tothe design of the engine block are, therefore, difficult to implement.

Further, the bearing caps or bearing support surfaces are madeseparately and machined to close tolerances. The bearing caps or bearingsupport surfaces are pre-assembled in the crankcase to enable machiningsuch as by flush grinding of the final bearing surfaces, and thendisassembled for inserting the crankshaft and for final crankshaftassembly.

Therefore, it is desirable to realize a large savings in the manufactureof automobile engines if the design and manufacture of the engine blockcould be simplified. It is also desired to provide a modular approach tomaking the engine structural components that contain the pistons,connecting rods, crankshaft, and bearing caps or bearing supportsurfaces. It is further desirable to separate the cylinder block portionof engine construction from the crankcase containing and assemblingportion of the engine. Therefore, there is a need in the art to providea simplified modular engine assembly that meets these desires.

SUMMARY OF THE INVENTION

It is, therefore, one object of the present invention to provide a newmodular engine assembly that is simplified to include bearing caps orbearing support surfaces.

To achieve the foregoing objects, the present invention is a modularengine assembly including a cylinder bore block, a cylinder headdisposed above the cylinder bore block, and a crankcase assemblydisposed below the cylinder bore block. The crankcase assembly includesan upper bearing carrier and a lower bearing carrier each having aplurality of bearing caps or bearing support surfaces therein beingintegral, unitary, and one-piece.

One advantage of the present invention is that a modular engine assemblyis provided for an internal combustion engine. Another advantage of thepresent invention is that the modular engine assembly has bearing capsor bearing support surfaces cast into a separate upper casting and lowercasting or a shape made from a molding or extrusion or a machined objectthat forms a clamshell. Yet another advantage of the present inventionis that the modular engine assembly eliminates the need for separatebearing caps or bearing support surfaces, which added some complexity tothe manufacturing process. Still another advantage of the presentinvention is that the modular engine assembly eliminates a midplate, onesealing surface, and cross bolts for locking the bearing caps or bearingsupport surfaces. A further advantage of the present invention is thatthe modular engine assembly has simpler fixturing and manufacturing ofthe engine block. Yet a further advantage of the present invention isthat the modular engine assembly has faster manufacturing throughputsince bearing caps or bearing support surfaces do not have to bepre-machined, assembled, machined, and then disassembled for thecrankshaft assembly. Still a further advantage of the present inventionis that the modular engine assembly has faster engine build sincebearing caps or bearing support surfaces do not have to be assembledindividually. Another advantage of the present invention is that themodular engine assembly has better dimensional control due to fewerparts. Yet another advantage of the present invention is that themodular engine assembly provides a stiffer engine due to fewerinterfaces. Still another advantage of the present invention is theabsence of a separate oil pan that can now be integrated into a lowercarrier and increases engine structure stiffness.

Other objects, features, and advantages of the present invention will bereadily appreciated, as the same becomes better understood, afterreading the subsequent description taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a modular engine assembly, according tothe present invention.

FIG. 2 is an exploded perspective view of the modular engine assembly ofFIG. 1.

FIG. 3 is a perspective view of a lower carrier of the modular engineassembly of FIG. 1.

FIG. 4 is a perspective view of an upper carrier of the modular engineassembly of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings and in particular FIG. 1, one embodiment of amodular engine assembly 10, according to the present invention, is shownfor a vehicle (not shown). The modular engine assembly 10 is of aninternal combustion type. The modular engine assembly 10 includes anextruded cylinder bore block 12 having at least one, preferably aplurality of cylindrical bores 14 spaced longitudinally therealong. Thecylinder bore block 12 is a shape that can be made from a casting,molding, shaping, or extrusion from a variety of materials such as castiron, aluminum, magnesium, or those materials with surface treatment.The cylinder bore block 12 is of a type disclosed in U.S. Pat. No.6,543,405, the disclosure of which is hereby incorporated by reference.

The modular engine assembly 10 also includes a cylinder head 16 disposedabove the cylinder bore block 12. The cylinder head 16 closes a top ofthe cylinder bores 14 to provide a combustion chamber in each bore 14 incooperation with a respective piston (not shown) reciprocating in thebore 14. The cylinder head 16 contains inlet and exhaust ports (notshown), and positions and supports intake and exhaust valves (notshown). The cylinder head 16 also contains a spark plug (not shown), inthe case of a spark ignition engine, and it often contains a fuelinjector (not shown). It should be appreciated that the components ofthe cylinder head 16 are not illustrated, for purposes of simplicity ofdisclosure, because their design, construction and operation does notnecessarily have to be altered by the use of the modular enginecomponents of the present invention.

The modular engine assembly 10 further includes a crankcase assembly,generally indicated at 18, disposed below the cylinder bore block 12.The cylinder bore block 12 and crankcase assembly 18 are separated by agasket 20. It should be appreciated that the modular engine assembly 10has a simplified modular architecture in that two 3-cylinder modules maybe joined to provide an in-line 6-cylinder engine and possibly a V-6engine.

Referring to FIGS. 1 through 4, the crankcase assembly 18 includes anupper carrier 22 and a lower carrier 24. The upper carrier 22 is a shapethat can be made from a casting, molding, shaping, or extrusion from avariety of materials such as cast iron, aluminum, magnesium, or thosematerials with surface treatment. The upper carrier 22 has an upper basewall 26 extending longitudinally and opposed side walls 28 extendingdownwardly and outwardly from the base wall 26. The upper carrier 22 hasa flange 30 extending outwardly from each of the side walls 28. Theupper carrier 22 has an end wall 32 at each longitudinal end thereof.The upper carrier 22 has a cavity 34 therein formed by the base wall 26,side walls 28, and end walls 32. The upper carrier 22 has a plurality ofbearing portions 36 disposed within and spaced longitudinally within thecavity 34. The bearing portions 36 extend from the base wall 26 and sidewalls 28 into the cavity 34. Each of the bearing portions 36 has acentrally located and generally arcuate recess 38 extending thereinforming a support surface 40. The upper carrier 22 has a plurality ofcylinder bore apertures 42 extending through the upper base wall 26 andaligned with the cylinder bores 14 of the cylinder bore block 12. Theupper carrier 22 also has a plurality of fastener apertures 44 spacedfrom the cylinder bore apertures 42 to receive fasteners 66 to bedescribed. The upper carrier 22 is a monolithic structure beingintegral, unitary, and one-piece.

The lower carrier 24 is a shape that can be made from a casting,molding, shaping, or extrusion from a variety of materials such as castiron, aluminum, magnesium, or those materials with surface treatment.The lower carrier 24 has a lower base wall 46 extending longitudinallyand opposed side walls 48 extending upwardly and outwardly from the basewall 46. The lower carrier 24 has a flange 50 extending outwardly fromeach of the side walls 48. The lower carrier 24 has an end wall 52 ateach longitudinal end thereof. The lower carrier 24 has a cavity 54therein formed by the base wall 46, side walls 48, and end walls 52. Thelower carrier 24 has a plurality of bearing portions 56 disposed withinand spaced longitudinally within the cavity 54. The bearing portions 56extend from the base wall 46 and side walls 48 into the cavity 54. Eachof the bearing portions 56 has a centrally located and generally arcuaterecess 58 forming a support surface 60. The lower carrier 24 also has aplurality of fastener apertures 62 to receive fasteners 66 to bedescribed. The lower carrier 24 is a monolithic structure beingintegral, unitary, and one-piece. It should be appreciated that thebearing portions 36 and 56 are identical to form a complete bearing capor bearing support surface for a crankshaft assembly 64 to be described.

The crankcase assembly 18 also includes a crankshaft assembly 64disposed between the upper carrier 22 and the lower carrier 24. Theupper carrier 22 and the lower carrier 24 form a clamshell and thebearing portions 36,56 support the crankshaft assembly 64 therein. Thecrankcase assembly 18 further includes a plurality of fasteners 66 suchas bolts extending through apertures (not shown) in the cylinder head16, cylinder bore block 12, and gasket 20, and through the fastenerapertures 44 in the upper carrier 22 and threadably engaging thefastener apertures 62 in the lower carrier 24. It should be appreciatedthat the fasteners 66 secure the upper carrier 22 and lower carrier 24together. It should also be appreciated that the cylinder bore block 12,cylinder head 14, and crankcase assembly 18 are structural parts of themodular engine assembly 10.

During manufacturing, the upper carrier 22 and lower carrier 24 arefaced off and held together. The support surfaces 40,60 are machinedwith one boring pass. The upper carrier 22 and lower carrier 24 areseparated and the crankshaft assembly 64 is assembled within the uppercarrier 22 and lower carrier 24. The upper carrier 22 and lower carrier24 are held together and the fasteners 66 secure the upper carrier 22and lower carrier 24 together. It should be appreciated that, when themodular engine assembly 10 is in an assembled condition, the cylinderbore block 12, cylinder head 16, and crankcase assembly 18 cooperate toenclose the crankshaft 64 in the crankcase assembly 18, four pistons(not shown) in cylinder bores 14, and four connecting rods (not shown)extending from the cylinder bores 14 into crankcase assembly 18.

The present invention has been described in an illustrative manner. Itis to be understood that the terminology, which has been used, isintended to be in the nature of words of description rather than oflimitation.

Many modifications and variations of the present invention are possiblein light of the above teachings. Therefore, within the scope of theappended claims, the present invention may be practiced other than asspecifically described.

1. A modular engine assembly comprising: a cylinder bore block; acylinder head disposed above said cylinder bore block; a crankcaseassembly disposed below said cylinder bore block, wherein said crankcaseassembly comprises an upper carrier and a lower carrier each having aplurality of bearing portions therein being integral, unitary, andone-piece; said upper carrier and said lower carrier each having aplurality of fastener apertures extending through said bearing portions;and a plurality of fasteners extending through said fastener aperturesto secure said upper carrier and said lower carrier together.
 2. Amodular engine assembly as set forth in claim 1 wherein said cylinderbore block is a shape that can be made from one of a casting, molding,shaping, and extrusion from one of a group of materials comprising castiron, aluminum, magnesium, or those materials with surface treatment. 3.A modular engine assembly as set forth in claim 1 wherein said uppercarrier is a shape that can be made from one of a casting, molding,shaping, or extrusion from one of a group of materials comprising castiron, aluminum, magnesium, or those materials with surface treatment. 4.A modular engine assembly as set forth in claim 1 wherein said lowercarrier is a shape that can be made from one of a casting, molding,shaping, or extrusion from one of a group of materials comprising castiron, aluminum, magnesium, or those materials with surface treatment. 5.A modular engine assembly as set forth in claim 1 wherein each of saidbearing portions has a recess forming a support surface.
 6. A modularengine assembly as set forth in claim 1 wherein said upper carrier has acavity therein and said bearing portions being disposed in said cavityand spaced longitudinally therealong.
 7. A modular engine assembly asset forth in claim 1 wherein said lower carrier has a cavity therein andsaid bearing portions being disposed in said cavity and spacedlongitudinally therealong.
 8. A modular engine assembly as set forth inclaim 1 wherein said upper carrier has a plurality of cylinder boreapertures extending therethrough.
 9. (canceled)
 10. (canceled) 11.(canceled)
 12. A modular engine assembly as set forth in claim 1including a crankshaft assembly disposed between said upper carrier andsaid lower carrier.
 13. A modular engine assembly comprising: a cylinderbore block; a cylinder head disposed above said cylinder bore block; acrankcase assembly disposed below said cylinder bore block, wherein saidcrankcase assembly comprises an upper carrier and a lower carrier; saidupper carrier and said lower carrier each having a plurality of bearingportions therein being integral, unitary, and one-piece; said uppercarrier having a plurality of first fastener apertures extendingtherethrough and said lower carrier having a plurality of secondfastener apertures therein; and a plurality of fasteners extendingthrough said cylinder head, said cylinder bore block, and said firstfastener apertures and into said second fastener apertures to securesaid cylinder head, said cylinder bore block, said upper carrier, andsaid lower carrier together.
 14. A modular engine assembly as set forthin claim 13 wherein said cylinder bore block is a shape that can be madefrom one of a casting, molding, shaping, and extrusion from one of agroup of materials comprising cast iron, aluminum, magnesium, or thosematerials with surface treatment.
 15. A modular engine assembly as setforth in claim 13 wherein said upper carrier is a shape that can be madefrom one of a casting, molding, shaping, or extrusion from one of agroup of materials comprising cast iron, aluminum, magnesium, or thosematerials with surface treatment.
 16. A modular engine assembly as setforth in claim 13 wherein said lower carrier is a shape that can be madefrom one of a casting, molding, shaping, or extrusion from one of agroup of materials comprising cast iron, aluminum, magnesium, or thosematerials with surface treatment.
 17. A modular engine assembly as setforth in claim 13 wherein each of said bearing portions has a recessforming a support surface.
 18. A modular engine assembly as set forth inclaim 13 wherein said upper carrier has a cavity therein and saidbearing portions being disposed in said cavity and spaced longitudinallytherealong.
 19. A modular engine assembly as set forth in claim 13wherein said lower carrier has a cavity therein and said bearingportions being disposed in said cavity and spaced longitudinallytherealong.
 20. A modular engine assembly as set forth in claim 13wherein said upper carrier has a plurality of cylinder bore aperturesextending therethrough.
 21. A modular engine assembly as set forth inclaim 13 including a crankshaft assembly disposed between said uppercarrier and said lower carrier.
 22. A modular engine assemblycomprising: a cylinder bore block; a cylinder head disposed above saidcylinder bore block; a crankcase assembly disposed below said cylinderbore block, wherein said crankcase assembly comprises an upper carrierand a lower carrier; each of said upper carrier and said lower carrierhaving a plurality of bearing portions therein; said bearing portionsbeing integral, unitary, and one-piece with said upper carrier and saidlower carrier, each of said bearing portions having a recess forming asupport surface; said upper carrier having a plurality of first fastenerapertures extending therethrough and said lower carrier having aplurality of second fastener apertures therein; a crankshaft assemblydisposed between said upper carrier and said lower carrier; and aplurality of fasteners extending through said cylinder head, saidcylinder bore block, and said first fastener apertures and into saidsecond fastener apertures to secure said cylinder head, said cylinderbore block, said upper carrier, and said lower carrier together.
 23. Amodular engine assembly as set forth in claim 22 wherein said cylinderbore block is a shape that can be made from one of a casting, molding,shaping, and extrusion from one of a group of materials comprising castiron, aluminum, magnesium, or those materials with surface treatment.24. A modular engine assembly as set forth in claim 22 wherein saidupper carrier is a shape that can be made from one of a casting,molding, shaping, or extrusion from one of a group of materialscomprising cast iron, aluminum, magnesium, or those materials withsurface treatment.
 25. A modular engine assembly as set forth in claim22 wherein said lower carrier is a shape that can be made from one of acasting, molding, shaping, or extrusion from one of a group of materialscomprising cast iron, aluminum, magnesium, or those materials withsurface treatment.